1. Field of the Invention
This invention relates generally to electrochemical machining and more specifically to a system and method for holding and releasing a workpiece for electrochemical machining.
2. Description of the Background Art
As set forth in the related application, a very small and consistent machining gap must be maintained between a workpiece and an electrode to electrochemically machine grooves into the workpiece effectively. In fact, the accuracy and consistency of the machining gap are oftentimes the most important factors in controlling the width and depth as well as the variability of electrochemically machined grooves. For example, in certain applications, the machining gap must be 20 microns or less and must not vary by more than 2 to 3 microns over the entire machining area for proper electrochemical machining of the grooves.
Current workpiece holders normally use mechanical clamps or some other mechanical means to secure the workpiece during electrochemical machining. One drawback to using these types of workpiece holders is that they tend to be too large and/or cumbersome to use where the machining gaps are 20 microns or smaller. Another drawback is that these types of workpiece holders create too much variability in the machining gap over the machining area (i.e., they cause the machining gap to vary by more than 3 microns over the machining area). Yet another drawback is that the mechanical clamps or other mechanical means used by current workpiece holders usually couple to the face of the workpiece that is being machined, thereby decreasing the amount of workpiece surface area available for machining.